A plug-in connector part of this kind comprises a housing that has a plug-in portion for plug-in connection to the mating plug-in connector part, and at least one contact element arranged on the plug-in portion and intended to electrically contact an associated mating contact element of the mating plug-in connector part.
A plug-in connector part of this kind can be used in particular as a charging plug or as a charging socket for charging an electrically powered vehicle (also referred to as an electric vehicle). In this case, for example, one end of a cable is connected to a charging station and the other end carries the plug-in connector part in the form of a charging plug which can be plugged into an associated mating plug-in connector part in the form of a charging socket on a vehicle, in order to thereby produce an electrical connection between the charging station and the vehicle.
Charging currents can in principle be transmitted as direct currents or as alternating currents, with in particular charging currents in the form of a direct current having a high current intensity, for example greater than 200 A or even greater than 300 A or even 350 A, and it being possible for these currents to lead to the cable, as well as a plug-in connector part connected to the cable, heating up.
A charging cable known from DE 10 2010 007 975 B4 has a cooling line which comprises a supply line and a return line for a coolant, and thus facilitates a flow of coolant back and forth in the charging cable. The cooling line of DE 10 2010 007 975 B4 is used both to dissipate heat losses produced in an energy storage of a vehicle, and to cool the cable per se.
In a charging system for charging an electric vehicle, heat is generated not only in the cable by means of which a charging plug is connected for example to a charging station, but is also generated at the charging plug and in particular inside the charging plug, for example on contact elements by means of which electrical contact with associated mating contact elements for example on a charging socket on an electric vehicle is produced when the charging plug is plugged into the charging socket. Contact elements of this kind, which are made of an electrically conductive metal material, for example a copper material, heat up when a charging current flows via the contact elements, the contact elements in principle being dimensioned depending on the charging current to be transmitted such that the contact elements have a sufficient current-carrying capacity, and a temperature increase on the contact elements is limited. In this case, a contact element is dimensioned so as to be larger the higher the charging current to be transmitted is.
However, there are limits to how much the size of the contact elements can be scaled with an increasing charging current, owing to the associated installation space requirement, the weight and the costs. There is therefore a need to transmit a high charging current using a contact element of relatively small dimensions.
In a charging system known from WO 2015/119791 A1 for charging an electric vehicle, coolant lines are guided inside a charging cable, by means of which coolant lines heat can also be dissipated from the region of a plug-in connector part connected to the charging cable.
In a charging system known from U.S. Pat. No. 5,909,099, charging currents are transmitted, using a transformer, via a core arranged in a plug-in connector part. A thermal conductor line for dissipating heat can be extended in the core.